Radio receiving circuit



MarchA 3, 1931. R. K. POTTER 1,794,418

RADIO RECEIVING CIRCUIT Original Filed Dec. 4, 1926 |NvENToR Kilmer BY zJ/i ATTORNEYb ilatented lidar. Si, ll

U'Ni'rED STATES PAFEN'` @FFECE lantern KIMBALI. IQTTER, or NEW YORK, N. Y., AssIGNoR To AMERICAN TELEPHONE ELERAPH COMPANY A CORPORATION OF NEW YORK RADIO RECEIVING CIRCUIT ,y Originalapplicationfiled December 4, 1926, Serial No. 152,659. Divided and this application filed September 20, 1928.

rlfhis application is a division of my copending application filed December 4, 1926, and vgiven Serial Number 152,659.

This invention relates to radio receiving 6 circuits, and more particularly to methods of and means for overcoming fading effects in radio reception.

It has been discovered that in night-time transmission of radio signals, at least at the wave lengths used in broadcasting, the signals sent from a point of transmission to any point of reception follow at leastV two major paths. One of these paths is a direct path between the transmitter and the rec-eiver, while the other path is devious and apparently of considerably greater length than the direct path. It appears further that these two major paths are in a common vertical plane between the transmitter and the receiver, and that the direct and indirect signal energy components receive-d at the distant point combine at a space angle in this plane.

It is the object of my invention to overlcome the fading effects due to the'existence of these two major transmission paths, and thus to provide for satisfactory reception during the periods when such fading is observed with the ordinary receiving system.

In general, I accomplish the desired result by establishing two receiving points 1n a I' 1 1MM emu-L um nm'nf. n#

serial No. 307,168.

follow both a direct path and an indirect path between the point of transmissionand a point of reception and indicates one desirable position of the two receivers;

Fig. 2 shows diagrammatically one arrangement oi. the receivers and associate-d circuits;

Fig. 3 comprises two vector diagrams in dicating the phase relations of Fig. 2;

Fig. 4 shows diagrammatically a second sent from T will reach the receivers R1 and Rgover a direct path DP. Also, the signals Will reach the receiver R1 over some such path as IPl and the receiver R2 over some such path as 1132. The horizontal separation of the two receivers may be made s uch that the signals received at the two points over either the direct or the indirect path ticalz'phme vluetvfveeni the point oftialismission and any point of reception,:twov radio? receivers substantially in a com-mon verticai piane withy the point of. transmission? said reeeivei's being; separated; onerom anotheivby a such that the: signals reoe-ivecl 'in the two yreceivers over the one path Wfl-1L, he .Completely ont odi phase and-,the signals received oveirhhe @the/rpath 'will1 have apositive ieetor sum1` f f l .6- A system for" receivingiadio signals off a given freqmeiaey which folio-W: both a i" 'est path; and; a-nr'iiiiiiifeet path in a single: vertice piane between the poi-at off' transmission and any point Vot' reception, said` system comprising; two radio receivers substantially in. a common vert-ic'alnpllane with the pointof transmission, saidZ -reee-ivei's being separated one. fi'om'another a distance such' that the signals received--Y in the' tivoreceivers over the onerpath will be complete-1y out oil pli-ase :met the signalsreee-i-Ved: over the other` path Wiili have a; positive veotoi suini-l, meansfor oomhiningrthe' outputs; ofi thev two receivers, a detest-oir, and means for impressie g' the oom.- hiiied' output the-Ixion'.V f

Ze In` a systemor i'eeeiving` radi-o sign-als oi a given freqrieiiey Wh-iehl foil-ow both direet @sich anch an' iridi-neeii paitbvi'ri a single vertical piane between. the point 01" transmission and? any .point mi reception, two@ rad-io re eeiweis suhstantialiy a common vertice-i plane with the point of Jtransmission, said reee'iveiis heilig separated one from., another'by ai distaiiefe such that.y the; signals received in the. twoizeeeivers: over; the; one path- Will be completely' m phase and* the signals Eeceived over' the other path will be completely out oifphase'. d' f 8. Af system: forieeeiving radio; signals of a: requeny which fol-low both a direct path andanindireet' path in a single; vertical plane'betweenthez point of titaiismissioia and any' point, of reception, said sys-tem# Compris ing 'two radiol receiv-eissubstantially in a eommori.- vertiealfV pianse with. the point.V ofv trans naissioi-r,v said" receivers: being separated` one ii-'omauother by a ciistance such thatthe sig;- iials received in the two receivers over vthe enepath, he Completely in phase, and the signals received over' the other path will he Completely out of'pfhase', means fol-r Combi-ning the outputs oi? the two: moei-versa a deteotor', stadi' nieams' erimpressin-g the combined oiit pas thereon. f

En testimonyv whereof I' havesignedf name'toithis specification, this: 14th of September' 1928.

' RALPH` KEMBALL- POTTER. 

